Image file formats supported by GDI +

You can use a number of standard formats to store bitmaps in disk files. GDI + supports the following various image file formats.

o Bitmap (BMP)

Bitmaps are standard formats that Windows uses to store device-independent and application-independent images. The file header determines the number of bits per pixel (1, 4, 8, 15, 24, 32, or all) of the specified bitmap file. Common bitmap files are 24 bits per pixel . Usually BMP files are not compressed and therefore not suitable for transmission over the Internet.

o Image Interchange Format (GIF)

GIF is a common picture format on Web pages. GIF applies To line graphics, pictures with solid blocks, and pictures with distinct boundaries between colors. GIF can be compressed and will not lose any information during the compression process, and the extracted image will be identical to the original image. The color of the GIF can be specified as transparent, so that the image can display the Web page of the image as the background color. The sequence of GIF images can be stored in a single file as an animated GIF. GI stores up to 8 bits per pixel, which limits them to 256 colors.

o Joint Image Expert Group (JPEG)

JPEG is a compression structure that is suitable for images of natural landscapes, such as scanned photos. Some information may be lost during compression, but the human eye cannot see the change. JPEG can store 24 bits per pixel, so they can display more than 16 million colors. JPEG does not support transparency effects or animations.

You can set the compression ratio of a JPEG picture file, but the higher the compression ratio (the smaller the file), the more information is lost. The difference between a picture and a source file resulting from a 20:1 compression ratio is often not recognized by the naked eye. A BMP picture and two JPEG images compressed from the BMP image are displayed. The first JPEG has a compression ratio of 4:1, and the second JPEG has a compression ratio of about 8:1.

JPEG compression does not apply to line graphics, real-color chunks, and distinct lines. A BMP and two JPEG and one GIF are displayed. These two JPEG and GIF are all compressed from BMP. GIF has a compression ratio of 4:1, a smaller jpeg of 4:1, and a larger JPEG of 8:3. Note that there is still a noticeable boundary between the lines in the GIF, but the boundaries in the JPEG appear blurry.

JPEG is a compression formula, not a file format. JPEG File Interchange Format (JFIF) is the usual format for storing and transferring pictures, which are compressed according to the JPEG formula. The jfif file that the Web browser displays will use the. jpg extension.

o exchangeable image file (Exif)

EXIF is the photo file format used for digital cameras. The EXIF file contains a picture that is compressed according to a JPEG specification. The Exif file also contains information about the photo (date of capture, shutter speed, exposure time, etc.) and camera information (manufacturer, model, etc.).

o Portable network picture (PNG)

The PNG format preserves the benefits of many GIF formats while providing more powerful features than GIF. PNG files and gif files also do not lose any information during the compression process. PNG files can store 8, 24, or 48-bit colors per pixel, as well as gray levels of 1, 2, 4, 8, or 16 bits per pixel. In contrast, GIF files can only use 1, 2, 4, or 8 bits per pixel. PNG files can also store the alpha value of each pixel, specifying how much the pixel blends with the background color.

PNG improves the functionality of the GIF progressive display image, and when PNG receives an image that is transmitted over the network, it can display better image effects. PNG files can contain gamma correction and color correction information so that the image can be correctly mapped to a variety of different display devices.

o Tagged Image File format (TIFF)

TIFF is a flexible and extensible format that is supported by various platforms and image processing applications. TIFF files can store images of any number of bits per pixel and can use a variety of compression algorithms. A single, multi-page TIFF file can store several images. Image-related information (scanner maker, host computer, compression type, orientation, sample per pixel, and so on) can also be stored in the file and can be arranged using markers. The TIFF format can be expanded as needed, if circumstances permit and new tags must be added.

Image file formats supported by GDI +